Dr. Mendoza is Assistant Professor of Pediatrics at Baylor College of Medicine and a general pediatrician. His long-term goal is to become an independent, patient-oriented investigator focusing on cancer prevention by reducing childhood obesity, with an emphasis on minority and low-income children. The applicant will accomplish this goal through patient-oriented research, formal mentoring by recognized experts, such as Drs. Tom Baranowski and Theresa Nicklas, and advanced, graduate-level coursework in cancer and obesity prevention, health promotion, qualitative methods, and advanced research methods. The applicant's research goal will be to conduct a group randomized controlled trial of a culturally adapted television (TV) reduction curriculum among Hispanic preschool children in order to reduce TV viewing and prevent excess weight gain. This research project addresses Hispanic children's higher rates of obesity and TV viewing, an important modifiable risk factor for obesity. The hypothesis is that decreasing TV viewing in Hispanic preschoolers will decrease excess weight gain. The applicant will test the effectiveness of the TV reduction curriculum, Fit 5 Kids, which has already been shown to decrease TV viewing in a population of predominantly white children from rural, upstate New York. Through separate pilot funding, Dr. Mendoza will have completed the cultural adaptation of the TV reduction curriculum, including a classroom feasibility trial and semi-structured interviews of parents and teachers. The first specific aim is to test the convergent validity of accelerometers, which provide a low burden and objective measure of physical inactivity, with standard parent-reported TV diaries among Hispanic children. The second specific aim is to determine the convergent validity of two neighborhood environment questionnaires among Hispanic children. The third specific aim is to develop a parent questionnaire, based on the Model of Goal Directed Behavior, to assess parents'behaviors to limit their children's TV viewing time. The fourth specific aim is to successfully recruit 144, 3-5 year old Hispanic children from 12 Head Start centers for a group randomized controlled study of the adapted Fit 5 Kids curriculum to evaluate its impact on reducing TV viewing and excess weight gain in Hispanic preschool children. Dr. Mendoza's research and career development activities will advance his goal of becoming a leading independent cancer prevention researcher focused on developing and evaluating programs to prevent childhood obesity and reduce cancer risk in ethnic minority and low-income children, with the aim of reducing lifetime cancer risk.